METHODS FOR HANDING OVER CALLS BETWEEN COMMUNICATION NETWORKS USING DISSIMILAR AIR INTERFACES

Description

Field of the Invention

[0001] The invention relates generally to mobile communication, and more particularly to inter-system handover of calls in progress.

Background of the invention

[0002] Mobile communication networks are in widespread use throughout metropolitan regions of the world, and have come to be common in many places. Over the years a variety of mobile communication services have been developed, including different radio air interfaces. Conventional mobile communication devices are designed for use with a particular air interface, but presently manufacturers are designing mobile communication devices that can access multiple communication networks having different air interfaces. Initial multi-mode mobile communication devices simply used dedicated hardware for different communication networks, and the device essentially had to be reset to switch over to a different air interface. Since then advances in integration have allowed manufacturers to design "all in one" mobile communication devices which can communicate over a variety of air interfaces, reusing circuitry for each of the air interfaces. Some of these devices were even "dual camp" designs which allowed the device to operate on two different communication networks at the same time.

[0003] On the other side of the air interface, the infrastructure and fixed equipment operated by communication service providers or operators, communication networks have been expanding and integrating as well. For one, most communication networks, in addition to conventional circuit mobile telephony, offer data services, including messaging and Internet access. Furthermore, communication network operators have been forming partnerships to support each others' subscribers, making it easy for users to roam from one system to another.

[0004] Presently, mobile circuit-switched voice communication is considered a mature technology. Much of the industry now is focusing on enhancing data communication, applications, and services. Efforts range from simply increasing data throughput to live voice and video streaming using Internet Protocol (IP) based communication. As a result there are a variety of competing mobile data service technologies available in the marketplace. Many of these technologies are standardized and specified by various standards organizations, such as, for example, the International Telecommunications Union (ITU). Standards are defined and published for present systems, but at the same time standards for future services as well as changes to existing services are also being undertaken in these organizations.

[0005] Two examples of data communication networks and protocols that are of interest in the industry, presently, are the Evolved Universal Terrestrial Radio Access Network (E-UTRAN), specified by the 3GPP group as 3GPP TS 36.300, and the Evolved Data Optimized (EV-DO) network specified as the cdma2000 High Rate Packet Data Air Interface Specification. Both of these specifications are well known in the art, and specify incompatible air interfaces. However, these systems can be connected on the network side of the air interface, potentially allowing inter-system call handover. However, even with data calls, considering there may be high quality of service (QoS) applications using the data call, minimizing handover delay is necessary to avoid packet loss. One way a data call could be handed over from one system to another would be for the mobile communication device to have two transceivers, one for each air interface. While a call or data session is being serviced on one, the other transceiver could be used to make arrangements with a base station of the other system to prepare for a handover. The dual transceiver approach, however, adds substantial cost the mobile communication device, as well as size and weight. Therefore there is a need for a method by which a call can be handed over from one communication network to a different communication network without incurring substantial delay.

[0006] US patent application publication no. 2003/0108006 describes a method and apparatus for effecting handoff between a first base station of a first cellular communications system to a second base station in a second, different, cellular communications system. The method comprises measuring at the mobile station a parameter of a signal transmitted by the first base station and a parameter of a signal transmitted by the second base station When the parameters reach a predetermined condition, a signal quality message is communicated from the mobile station via the first base station to the first mobile switching control station of the first cellular communications system, which responds by generating information for a channel request message for a second mobile switching control station of the second cellular communications system and transmitting the generated information to the mobile station The mobile station generates from the information a channel request message and transmits the message to the second mobile switching control station. The second mobile switching control station generates channel information identifying a channel in the second communications system for the mobile station so that the handoff may be effected.

[0007] Universal Mobile Telecommunications System (UMTS); Radio Resource Control (RRC); Protocol specification (3GPP TS 25.331 V7.4.0 Release 7, paragraphs 8.3.7 to 8.3.9 describes procedures for inter-RAT handover from UTRAN and inter-RAT cell reselection to UTRAN.

SUMMARY OF THE INVENTION

[0008] In accordance with the present invention, there are provided methods of performing call handover as recited in the accompanying claims.

[0009] The present invention discloses in one embodiment of the invention a method of performing call handover of a call in progress at a mobile communication device between networks having dissimilar air interface. From the perspective of the first communication network the method commences upon receiving from the mobile communication device at a base station of a first communication network a neighbor cell measurement. The neighbor cell measurement is performed by the mobile communication device on a neighbor cell belonging to the first communication network. The base station to which the mobile communication device is connected then determines that the neighbor cell measurement indicates handover to a second communication network is desirable. However, the second communication network uses a different air interface. The base station the commences transmitting to the mobile communication device a neighbor cell list including at least one neighbor cell of the second communication network. The mobile communication device undertakes the measurements by tuning away from the present serving base station to receive signals from the indicated neighbor cells of the second communication network. The mobile communication device also transmits its session profile, including session control and protocol parameters desired by the mobile communication device for the call, to the base station. The parameters indicate the resources needed to support the present call on the second communication network. Upon making the measurements on the base stations of the second communication network, the mobile communication device transmits the results to its present serving base station. The base station then commences a handover negotiation with a radio network controller of the second communications network. The radio network controller evaluates the information and decides whether the request can be supported given presently available resources. A counteroffer may be proposed by the radio network controller. Once the radio network controller decides upon a base station and communication parameters, the radio network controller formulates a handover grant message. The grant message includes a target base station identifier and connection parameters. The target base station identifier corresponds to the target base station of the second communication network to which the call will be handed. The radio network controller transmits grant message back to the base station of the first communication network presently handling the call. The grant information is then transmitted to the mobile communication device, which uses the target base station identifier to handover to the target base station of the second communication network according to the connection parameters.

[0010] From the radio network controller's perspective, the invention provides for a method of performing call handover from the first communication network to the second communication network, where the radio network controller is in the second communication network, and the two communication networks use different air interfaces. The method commences upon receiving a handover request at the radio network controller from a base station of the first communication network via a mobility management entity of the first communication network. The base station making the request is the base station presently servicing the call. The handover request includes at least one neighbor cell measurement performed by a mobile communication device on a base station of the second communication network, as well as a session profile. The session profile includes session control and protocol parameters used by the mobile communication device for the call. The radio network controller then commences selecting a base station of the second communication network to receive the handover based on the session profile and available resources of the second communication network. The radio network controller generates a grant message which includes an identifier to be used by the mobile communication device upon handover, a target base station identifier of a target base station of the second communication network which will receive the handover, and connection parameters to be used by the mobile communication device upon connecting to the base station of the second communication network. The radio network controller then transmits the grant message back to the requesting base station, which relays the information to the mobile communication device. The mobile communication device then uses the information to handover the call to the second communication network using the air interface of the second communication network.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] There are shown in the drawings, embodiments which are presently preferred, it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.

[0012] FIG. 1 shows a system diagram of two communication networks' serving cells where the two communication networks use differing air interfaces to facilitate wireless mobile communication for mobile communication devices;

[0013] FIG. 2 shows a network architecture diagram of two communication networks operating in accordance with an embodiment of the invention; and

[0014] FIG. 3 shows a signal flow diagram of a method of performing call handover between communication networks having different air interfaces, in accordance with an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0015] While the specification concludes with claims defining features of the invention that are regarded as novel, it is believed that the invention will be better understood from a consideration of the description in conjunction with the drawings. As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. Further, the terms and phrases used herein are not intended to be limiting but rather to provide an understandable description of the invention.

[0016] Referring now to FIG. 1, there is shown a system diagram 100 of two communication networks' serving cells. A present serving cell 102 is operated by a base station 104, which facilitates an air interface according to a defined radio communications protocol in the vicinity of the base station, as is well know in the art. A mobile communication device 106 is designed and configured to operate according to the air interface so that it may engage in communication activity via the base station. The base station is part of a communication network which includes base stations and other fixed equipment. Neighbor cells 108, 110, which are part of the same communication network to which base station 104 belongs, and operate using the same air interface as used by base station 104. The mobile communication device 106 can travel from one cell to another through the region, with service for the mobile communication device being handed over from once cell to the next. The process of handover is well known, and generally involves the mobile communication device making measurements of the signals transmitted by neighbor cells, selecting a target cell from the neighbor cells based on the measurements, and then redirecting communication service in the communication network to the new serving cell while the mobile communication device retunes to the new cell frequency.

[0017] In addition to neighbor cells 108 and 110, another cell 112 also neighbors the present serving cell, but it is not part of the same communication network to which base station 104 belongs, as indicated by the dashed line bordering cell 112. Cell 112 further operates using an air interface that is substantially different that that of cells 102, 108, and 110. In one embodiment of the invention, cells 102, 108, and 110 may be operated according the "Evolved Universal Terrestrial Radio Access Network" (E-UTRAN) specification, and cell 112 may be operated in accordance with the "cdma2000 High Rate Packet Data Air Interface Specification," and communication activity being conducted is a data communication activity, such as, for example, voice over IP (VoIP) calling.

[0018] If the mobile communication device 106 is traveling in the direction of either cell 108 or 110, then service may routinely be handed over to the appropriate cell. However, if the mobile communication device is moving away from cells 102, 108, and 110 towards an area where the communication network to which those cell belong doe not support service but where service is provided by a second communication network operating cell 112, then it is beneficial to hand communication service over to cell 112. However, if the mobile communication device is solely responsible for contacting cell 112 to arrange for handover, the resulting interruption in service would not be acceptable. This assumes the mobile communication device uses a single transceiver and does not have the resources to communicate with both communication networks at the same time, which allows for a less expensive and smaller mobile communication device. The delay comes from the fact that the systems use different mobile identifiers, different channel structure, different session and protocol stack, and so on.

[0019] Referring now to FIG. 2, there is shown a network architecture diagram 200 of two communication networks operating in accordance with an embodiment of the invention. A mobile communication device 202 is presently connected to a first communication network, such as one operated in accordance with the E-UTRAN specification. The mobile communication device 202 communicates with a base station 204, which may be a base station operated in accordance with E-UTRAN specification of "Evolved Node B," or simply "eNB." The base station 204 communicates with a core network 206, which may be an evolved core as specified by the E-UTRAN specification. In particular the base station is operably coupled to a serving system architecture evolution gateway (SAE GW) 208. The serving SAE GW facilitates communication between base stations and packet data network SAE gateway (PDN SAE GW). The PDN SAE GW facilitates packet data communication between the communication network and a wide area packet network 211.

[0020] The base station 204 may have a neighboring base station or neighbor cell established by base station 212. In the present example, the neighbor base station 212 is coupled to a different serving SAE GW 218. In some circumstances mobile communication device 202 may travel away from base station 204 and towards base station 212, prompting a handover from base station 204 to base station 212. This sort of intra-system handover is routine, and is facilitated by mobility management entities (MME) 214 and 216. As shown in the present example, each base station has a control link, as indicated by the dashed lines, to its respective MME. The MMEs facilitate signaling between the base stations to coordinate handovers, among other activities.

[0021] In the second communication network there are base stations such as base station 220, known as a base transceiver site (BTS). In the present example, the second network may be one operated and configured in accordance with the "cdma2000 High Rate Packet Data Air Interface Specification," referred to as evolution data optimized or EV-DO system. Thus, according to an embodiment of the invention, the first communication network is an E-UTRAN system and the second system is an EV-DO system. The base station of the second network is operably coupled to a radio network controller (RNC) 222 which facilitates mobility management and other resource management functions. The RNC is coupled to a packet data service node 224 which, in turn, is coupled to the serving SAE gateway 208, providing a common point between the two systems. A control link is established between the MME 214 and the RNC 222 which facilitates the inter-system handover in accordance with the invention.

[0022] According to the invention, as signal conditions deteriorate for the mobile communication device while operating in the first communication network, indicating a handover is desirable, and more specifically that handover to the second communication network is desirable due to a lack of suitable target cells in the first communication network, the present serving base station 204 communicates with the RNC 222 via the MME 214 to negotiate handover of the mobile communication device and call to a suitable base station of the second communication network.

[0023] Referring now to FIG. 3, there is shown a signal flow diagram 300 of a method of performing call handover between communication networks having different air interfaces, in accordance with an embodiment of the invention. In keeping with the examples discussed with respect to FIG. 2, the method as illustrated by FIG. 3 involves a handover from an E-UTRAN system to an EV-DO system of a data call being commenced by a mobile communication device. The invention facilitates such inter-system handover by facilitating acquisition of a unicast access terminal identifier (UATI) to be used by the mobile communication device with the target EV-DO system, perform session configuration, and connect with the target base station of the DO network on a dedicated traffic channel with a minimum of interruption. The diagram shows exemplary signal flow between a mobile communication device 302, eNB or base station of a first communication network 304, mobility management entity 306, radio network controller 308, and a target base station of a second communication network 310, such as a BTS of a DO network.

[0024] The present example commences with the mobile communication device involved in a data call in the first communication network. In the course of routine operation, the mobile communication device has received from the first communication network base station a neighbor cell list of intra-system neighbor cells adjacent to the present serving cell. The mobile communication device uses this information to periodically scan the neighbor cells for signal strength and channel conditions. The neighbor cell information is periodically transmitted to the present serving base station (312) along with the signal conditions of the present serving base station. In an intra-system handover, the base station would evaluate the present signal conditions between the mobile communication device and the base station, and if the signal conditions indicate a handover is necessary, the base station may select a target base station from among its neighbor cells within the same communication network, and commence a routine handover. However, according to the present exemplary embodiment of the invention, the base station, or other network entity, evaluates the neighbor cell information (314) and determines that signal conditions indicate a handover is needed, and that there are no intra-system cells suitable for receiving the handover, based on the measurements received from 312.

[0025] In response, according to the invention, the serving base station provides cell information of at least one nearby cell of a second communication network, such as an EV-DO system. The present serving base station may have this information as a result of an agreement between network operators, for example. It will be appreciated that, although shown here as being transmitted to the mobile communication device after the decision 314 to evaluate inter-system handover conditions, the neighbor cell information for cell of the second communication network maybe transmitted earlier, and upon making the decision 314, the base station merely commands the mobile communication device to make the evaluations at 316. To facilitate inter-system handover, the mobile communication device also provides session profile information and protocol parameters 318 to the base station for the present call. This information is necessary so that the same level of communication may be acquired on the second communication network, as required by the application in the mobile communication device.

[0026] Upon receiving the neighbor cell information for neighboring cells of the second communication network, the mobile communication device then commences measuring signal conditions 320 of the indicated neighbor cells of the second communication network. This involves reconfiguring the transceiver of the mobile communication device to receive the control signals transmitted by the base stations of the second communication network since they are operated according to a different air interface than the first communication network. The results of the measurements of the signal conditions of the bases stations of the second communication network are transmitted back to the serving base station of the first communication network (321). If at least one of the measured cells of the second communication network is deemed to be a suitable target for handover, the base station 304 will commence an inter-system handover.

[0027] The inter-system handover is performed via the MME 306. The present serving base station transmits to the MME the session profile and protocol parameters (322), which are forwarded (324) by the MME to the RNC 308 of the second communication network. The RNC and the handover candidate base station or stations evaluates the information (326) and the present resources available at the handover candidate base station or stations to determine which base station should receive the handover. Alternatively, the RNC may make a counter offer if it cannot support the request as initially specified.

[0028] Once the decision is made as to the parameters and identity of the target base station of the second communication network, the RNC transmits the information in a grant message back to the serving base station through the MME (330, 332). At the same time, the RNC may inform the target base station of the impending handover 328. The information provided by the RNC may include, for example, a unicast access terminal identifier (UATI) to be used by the mobile communication device in communicating with the second communication network; the target base station's sector ID including network address and node address; random access parameters such as access cycle duration, access preamble length, open loop adjustment, initial access probe adjustment, the number of access probes in a probe sequence, increase in power between probes, and backoff persistence probability between probe sequences; the protocol set to be used in the session, such as relevant protocol parameters like authentication key lengths; dedicated control and traffic channel parameters such as the medium access control (MAC) index assigned to the mobile communication device, the acknowledgement channel and data rate channel gain relative to the reverse pilot channel, and the data rate control cover corresponding to the target base station; and a random access required flag to indicate whether random access is required by the mobile communication device to access the target base station of the second communication network. These parameters and information are sent by the serving base station to the mobile communication device (334), and the serving base station may indicate an action time for the mobile communication device to make the switch to the indicated target base station of the second communication network.

[0029] The Random Access Required flag is determined by the target base station and RNC of the second communication network. The decision may be made based on the reverse link load on the second communication network, on the expected time interval it takes to complete the handover from the first network to the second network, or on the QoS or service level of the ongoing call.

[0030] The mobile communication device, upon receiving the information, then commences an access procedure with the target base station 310 using indicated parameters, and using the air interface of the second communication network. If the random access required flag is set, the mobile communication device will first go through a random access procedure, using the random access parameters carried in the handover grant message, and after receiving acknowledgement from the target base station of the second network, switches to the assigned dedicated traffic and control channel on the second network. Otherwise, the mobile communication device will bypass the random access procedure and switch to the assigned dedicated traffic and control channel on the second network using the dedicated control and traffic channel parameters carried in the handover grant message. Upon successful admission the call is successfully handed over, and the information is rerouted in the core network from the first communication network to the second communication network.

[0031] This invention can be embodied in other forms. Accordingly, reference should be made to the following claims, rather than to the foregoing specification, as indicating the scope of the invention.

Claims

1. A method (300) of performing call handover of a call in progress at a mobile communication device between networks having dissimilar air interfaces, comprising:

receiving (312) from the mobile communication device at a base station of a first communication network first neighbor cell measurement, the first neighbor cell measurement performed by the mobile communication device on a neighbor cell of the base station of the first communication network;

determining (314), at the base station of the first communication network, that the neighbor cell measurement indicates handover to a second communication network is desirable, wherein the second communication network uses a different air interface than the first communication network;

transmitting (316) to the mobile communication device from the base station of the first communication network a neighbor cell list including at least one neighbor cell of a second communication network;

receiving (318) from the mobile communication device at the base station of the first communication network a session profile including session control and protocol parameters desired by the mobile communication device for the call on the second communication network;

receiving (321) from the mobile communication device at the base station of the first communication network a neighbor cell measurement of the at least one neighbor cell of the second communication network;

commencing (322, 324) a handover negotiation with a radio network access controller of the second communication network from the base station of the first communication network;

receiving (330, 332) from the radio access controller at the base station of the first communication network a handover grant message including a target base station identifier and connection parameters, the target base station identifier corresponding to a target base station of the second communication network; and

transmitting (334) the target base station identifier and connection parameters to the mobile communication device;

wherein the mobile communication device uses the target base station identifier to handover to the target base station of the second communication network according to the connection parameters.

2. A method of performing call handover as defined in claim 1, wherein the first communication network is an Evolved Universal Terrestrial Radio Access Network, E-UTRAN, system, and the second communication network is anEvolution Data Optimised, EV-DO, system.

3. A method of performing call handover as defined in claim 1, wherein the base station of the first network and the radio access network controller of the second network communicate through a mobility management entity.

4. A method of performing call handover as defined in claim 1, wherein commencing (322, 324) the handover negotiation with the radio network access controller includes sending to the radio access network controller a session profile including session control and protocol parameters used by the mobile communication device for the call.

5. A method of performing call handover as defined in claim 1, wherein upon commencing (322, 324) the handover negotiation, the radio access network controller selects (326) the base station of the second network to which the call will be handed over.

6. A method of performing call handover as defined in claim 1, wherein the handover grant message further includes an assigned identifier to be used by the mobile communication device.

7. A method of performing call handover as defined in claim 1, wherein the handover grant message further includes a sector identifier corresponding to a sector of the target base station.

8. A method of performing call handover as defined in claim 1, wherein the handover grant message further includes random access parameters to be used by the mobile communication device upon commencing the handover to the target base station.

9. A method of performing call handover as defined in claim 1, wherein the handover grant message further includes dedicated control and traffic channel parameters to be used by the mobile communication device upon commencing the handover to the target base station.

10. A method of performing call handover as defined in claim 1, wherein the handover grant message further includes a random access required flag to indicate whether a random access procedure is to be used by the mobile communication device upon commencing the handover to the target base station.

11. A method (300) of performing call handover from a first communication network to a second communication network, wherein the first and second communication networks use different air interfaces, the method comprising:

receiving (322, 324) a handover request at a radio network controller of the second communication network from a base station of the first communication network via a mobility management entity of the first communication network, the handover request including at least one neighbor cell measurement performed by a mobile communication device operating in the first communication network of a base station of the second communication network and further including a session profile of the mobile communication device including session control and protocol parameters used by the mobile communication device for the call;

selecting (326), at the radio network controller, a base station of the second communication network to receive the handover based on session profile and available resources of the base station of the second communication network,

generating a grant message at the radio network controller, the grant message including an identifier to be used by the mobile communication device upon handover, a target base station identifier of a target base station of the second communication network which will receive the handover, and connection parameters to be used by the mobile communication device upon connecting to the base station of the second communication network; and

transmitting (330, 332), from the radio network controller to the base station of the first communication network, the handover grant message;

wherein the mobile communication device uses the target base station identifier to handover to the target base station of the second communication network according to the connection parameters.

12. A method of performing call handover as defined in claim 11, wherein the first communication network is an Evolved Universal Terrestrial Radio Access Network, E-UTRAN, system, and the second communication network is a Evolution Data Optimised, EV-DO, system.

13. A method of performing call handover as defined in claim 11, wherein the handover grant message further includes a sector identifier corresponding to a sector of the target base station.

14. A method of performing call handover as defined in claim 11, wherein the handover grant message further includes random access parameters to be used by the mobile communication device upon commencing the handover to the target base station.

15. A method of performing call handover as defined in claim 11, wherein the handover grant message further includes dedicated control and traffic channel parameters to be used by the mobile communication device upon commencing the handover to the target base station.

16. A method of performing call handover as defined in claim 11, wherein the handover grant message further includes a random access required flag to indicate whether a random access procedure is to be used by the mobile communication device upon commencing the handover to the target base station.

Ansprüche

1. Verfahren (300) zur Ausführung einer Gesprächsübergabe einer bestehenden Verbindung an einer mobilen Kommunikationsvorrichtung zwischen Netzwerken, welche unterschiedliche Luftschnittstellen aufweisen, wobei das Verfahren die folgenden Schritte aufweist:

Empfang (312) von der mobilen Kommunikationsvorrichtung an einer Basisstation eines ersten Kommunikationsnetzwerks eine erste Nachbarzellmessung, wobei die erste Nachbarzellmessung von der mobilen Kommunikationsvorrichtung an einer Nachbarzelle der Basisstation des ersten Kommunikationsnetzwerks durchgeführt wird;

Bestimmung (314) an der Basisstation des ersten Kommunikationssnetzwerks, dass die Nachbarzellmessung eine erwünschte Gesprächsübergabe an ein zweites Kommunikationsnetzwerk anzeigt, wobei das zweite Kommunikationssnetzwerk eine unterschiedliche Luftschnittstelle als das erste Kommunikationsnetzwerk verwendet;

Übertragung (316) einer Nachbarzellenliste einschließlich mindestens einer Nachbarzelle eines zweiten Kommunikationsnetzwerks von der Basisstation des ersten Kommunikationsnetzwerks an die mobile Kommunikationsvorrichtung;

Empfang (318) von der mobilen Kommunikationsvorrichtung an der Basisstation des ersten Kommunikationsnetzwerks eines Sitzungsprofils einschließlich Sitzungssteuerungs- und Sitzungsprotokoll-Parameter, welche von der mobilen Kommunikationsvorrichtung für den Anruf auf dem zweiten Kommunikationsnetzwerk gewünscht werden;

Empfang (321) von der mobilen Kommunikationsvorrichtung an der Basisstation des ersten Kommunikationsnetzwerks einer Nachbarzellmessung der mindestens einen Nachbarzelle des zweiten Kommunikationsnetzwerks;

Starten (322, 324) einer Gesprächsübergabe-Verhandlung mit einer Funknetz-Zugriffssteuerung des zweiten Kommunikationsnetzwerks von der Basisstation des ersten Kommunikationsnetzwerks;

Empfang (330, 332) von der Funknetz-Zugriffssteuerung an der Basisstation des ersten Kommunikationsnetzwerks einer Gesprächsübergabe-Bewilligungs- bzw. Freigabenachricht einschließlich einer Zielbasisstations-Kennung und einschließlich Verbindungsparametern, wobei die Zielbasisstations-Kennung einer Zielbasisstation des zweiten Kommunikationsnetzwerks entspricht; und

Übertragung (334) der Zielbasisstations-Kennung und der Verbindungsparameter an die mobile Kommunikationsvorrichtung;

dadurch gekennzeichnet, dass die mobile Kommunikationsvorrichtung die Zielbasisstations-Kennung für die Gesprächsübergabe an die Zielbasisstation des zweiten Kommunikationsnetzwerks gemäß den Verbindungsparametern verwendet.

2. Verfahren zur Durchführung einer Gesprächsübergabe nach Anspruch 1, dadurch gekennzeichnet, dass das erste Kommunikationsnetzwerk ein Evolved Universal Terrestrial Radio Access Network bzw. E-UTRAN-System ist, und dass das zweite Kommunikationsnetzwerk ein Evolution Data Optimised bzw. EV-DO-System ist.

3. Verfahren zur Durchführung einer Gesprächsübergabe nach Anspruch 1, dadurch gekennzeichnet, dass die Basisstation des ersten Netzwerks und die Funkzugriffssteuerung des zweiten Netzwerks über ein Mobilitätsmanagement-Organ kommunizieren.

4. Verfahren zur Durchführung einer Gesprächsübergabe nach Anspruch 1, dadurch gekennzeichnet, dass der Beginn (322, 324) der Gesprächsübergabe-Verhandlung mit der Funknetz-Zugriffssteuerung das Senden eines Sitzungsprofils einschließlich Sitzungssteuerungs- und Sitzungsprotokoll-Parametern, welche von der mobilen Kommunikationsvorrichtung für den Anruf verwendet werden, an die Funknetz-Zugriffssteuerung einschließt.

5. Verfahren zur Durchführung einer Gesprächsübergabe nach Anspruch 1, dadurch gekennzeichnet, dass nach Beginn (322, 324) der Gesprächsübergabe-Verhandlung die Funknetz-Zugriffssteuerung die Basisstation des zweiten Netzwerks auswählt (326), an welche das Gespräch übergeben wird.

6. Verfahren zur Durchführung einer Gesprächsübergabe nach Anspruch 1, dadurch gekennzeichnet, dass die Gesprächsübergabe-Bewilligungsnachricht des Weiteren eine zugewiesene Kennung einschließt, welche von der mobilen Kommunikationsvorrichtung verwendet werden soll.

7. Verfahren zur Durchführung einer Gesprächsübergabe nach Anspruch 1, dadurch gekennzeichnet, dass die Gesprächsübergabe-Bewilligungsnachricht des Weiteren eine Sektorkennung einschließt, welche einem Sektor der Zielbasisstation entspricht.

8. Verfahren zur Durchführung einer Gesprächsübergabe nach Anspruch 1, dadurch gekennzeichnet, dass die Gesprächsübergabe-Bewilligungsnachricht des Weiteren Zufallszugriff-Parameter einschließt, welche von der mobilen Kommunikationsvorrichtung nach Beginn der Gesprächsübergabe an die Zielbasisstation verwendet werden sollen.

9. Verfahren zur Durchführung einer Gesprächsübergabe nach Anspruch 1, dadurch gekennzeichnet, dass die Gesprächsübergabe-Bewilligungsnachricht des Weiteren fest zugeordnete Steuer- und Verkehrskanal-Parameter einschließt, welche von der mobilen Kommunikationsvorrichtung nach Beginn der Gesprächsübergabe an die Zielbasisstation verwendet werden sollen.

10. Verfahren zur Durchführung einer Gesprächsübergabe nach Anspruch 1, dadurch gekennzeichnet, dass die Gesprächsübergabe-Bewilligungsnachricht des Weiteren ein benötigtes Zufallszugriffs-Flag einschließt, um anzuzeigen, ob ein Zufallszugriffs-Verfahren von der mobilen Kommunikationsvorrichtung nach Beginn der Gesprächsübergabe an die Zielbasisstation verwendet werden soll.

11. Verfahren (300) zur Durchführung einer Gesprächsübergabe von einem ersten Kommunikationsnetzwerk an ein zweites Kommunikationsnetzwerk, dadurch gekennzeichnet, dass das erste und das zweite Kommunikationsnetzwerk unterschiedliche Luftschnittstellen verwenden, wobei das Verfahren die folgenden Schritte aufweist:

Empfang (322, 324) einer Gesprächsübergabe-Anfrage an einer Funknetzsteuerung des zweiten Kommunikationsnetzes von einer Basisstation des ersten Kommunikationsnetzwerks über ein Mobilitätsmanagement-Organ des ersten Kommunikationsnetzwerks, wobei die Gesprächsübergabe-Anfrage mindestens eine von der mobilen Kommunikationsvorrichtung durchgeführte Nachbarzellmessung einschließt, wobei die mobile Kommunikationsvorrichtung in dem ersten Kommunikationsnetzwerk einer Basisstation des zweiten Kommunikationsnetzwerks arbeitet, und wobei die Gesprächsübergabe-Anfrage des Weiteren ein Sitzungsprofil der mobilen Kommunikationsvorrichtung einschließlich Sitzungssteuerungs- und Sitzungsprotokoll-Parameter einschließt, welche von der mobilen Kommunikationsvorrichtung für das Gespräch bzw. den Anruf verwendet werden;

Auswahl (326) an der Funknetzsteuerung einer Basisstation des zweiten Kommunikationsnetzwerks für den Empfang der Gesprächsübergabe basierend auf einem Sitzungsprofil und verfügbaren Betriebsmitteln der Basisstation des zweiten Kommunikationsnetzwerks;

Erzeugung einer Bewilligungsnachricht an der Funknetzsteuerung, wobei die Bewilligungsnachricht eine von der mobilen Kommunikationsvorrichtung nach Gesprächsübergabe zu verwendende Kennung, eine Zielbasisstations-Kennung einer Zielbasisstation des zweiten Kommunikationsnetzwerks, welches die Gesprächsübergabe empfängt, und Verbindungsparameter einschließt, welche von der mobilen Kommunikationsvorrichtung nach Anschluss an die Basisstation des zweiten Kommunikationsnetzwerks verwendet werden sollen; und

Übertragung (330, 332) der Gesprächsübergabe-Bewilligungsnachricht von der Funknetzsteuerung an die Basisstation des ersten Kommunikationsnetzwerks;

dadurch gekennzeichnet, dass die mobile Kommunikationsvorrichtung die Zielbasisstations-Kennung zur Übergabe des Gesprächs an die Zielbasisstation des zweiten Kommunikationsnetzwerks gemäß den Verbindungsparametern verwendet.

12. Verfahren zur Durchführung einer Gesprächsübergabe nach Anspruch 11, dadurch gekennzeichnet, dass das erste Kommunikationsnetzwerk ein Evolved Universal Terrestrial Radio Access Network bzw. E-UTRAN-System ist, und dass das zweite Kommunikationsnetzwerk ein Evolution Data Optimised bzw. EV-DO-System ist.

13. Verfahren zur Durchführung einer Gesprächsübergabe nach Anspruch 11, dadurch gekennzeichnet, dass die Gesprächsübergabe-Bewilligungsnachricht des Weiteren eine Sektorkennung einschließt, welche einem Sektor der Zielbasisstation entspricht.

14. Verfahren zur Durchführung einer Gesprächsübergabe nach Anspruch 11, dadurch gekennzeichnet, dass die Gesprächsübergabe-Bewilligungsnachricht des Weiteren Zufallszugriffs-Parameter aufweist, welche von der mobilen Kommunikationsvorrichtung nach Beginn der Gesprächsübergabe an die Zlelbasisstation verwendet werden sollen.

15. Verfahren zur Durchführung einer Gesprächsübergabe nach Anspruch 11, dadurch gekennzeichnet, dass die Gesprächsübergabe-Bewilligungsnachricht des Weiteren fest zugeordnete Steuer- und Verkehrskanal-Parameter einschließt, welche von der mobilen Kommunikationsvorrichtung nach Beginn der Gesprächsübergabe an die Zielbasisstation verwendet werden sollen.

16. Verfahren zur Durchführung einer Gesprächsübergabe nach Anspruch 11, dadurch gekennzeichnet, dass die Gesprächsübergabe-Bewilligungsnachricht des Weiteren ein benötigtes Zufallszugriffs-Flag einschließt, um anzuzeigen, ob ein Zufallszugriffs-Verfahren von der mobilen Kommunikationsvorrichtung nach Beginn der Gesprächsübergabe an die Zielbasisstation verwendet werden soll.

Revendications

1. Procédé (300) pour exécuter un transfert d'un appel en cours à un dispositif de communication mobile entre des réseaux ayant des interfaces radio dissemblables, comprenant:

recevoir (312) du dispositif de communication mobile à une station de base d'un premier réseau de communication une première mesure de cellule de voisinage, la première mesure de cellule de voisinage étant exécutée par le dispositif de communication mobile sur une cellule de voisinage de la station de base du premier réseau de communication;

déterminer (314), à la station de base du premier réseau de communication que la mesure de la cellule de voisinage indique que le transfert à un deuxième réseau de communication est souhaitable, où le deuxième réseau de communication utilise une interface d'air différente que le premier réseau de communication;

transmettre (313) au dispositif de communication mobile de la station de base du premier réseau de communication une liste de cellules de voisinage incluant au moins une cellule de voisinage d'un deuxième réseau de communication;

recevoir (318) du dispositif de communication mobile à la station de base du premier réseau de communication un profil de session incluant des paramètres de commande et de protocole de session souhaités par le dispositif de communication mobile pour l'appel sur le deuxième réseau de communication;

recevoir (321) du dispositif de communication mobile à la station de base du premier réseau de communication une mesure de cellule de voisinage de la au moins une cellule de voisinage du deuxième réseau de communication;

commencer (322, 324) une négociation de transfert avec un dispositif de commande d'accès au réseau radio du deuxième réseau de communication de la station de base du premier réseau de communication;

recevoir (330, 332) du dispositif de commande d'accès radio à la station de base du premier réseau de communication un message d'accord de transfert incluant un identifiant de station de base cible et des paramètres de connection, l'identifiant de station de base cible correspondant à une station de base cible du deuxième réseau de communication; et

transmettre (334) l'identifiant de station de base cible et les paramètres de connection au dispositif de communication mobile;

où le dispositif de communication mobile utilise l'identifiant de la station de base cible pour le transfert à la station de base cible du deuxième réseau de communication en accord avec les paramètres de connection.

2. Procédé pour exécuter un transfert d'appel tel que défini dans la revendication 1, où le premier réseau de communication est un Système de Réseau d'Accès Radio Terrestre Universel Evolué, E-UTRAN, et le deuxième réseau de communication est un système Optimisé de Données d'Evolution, EV-DO.

3. Procédé pour exécuter un transfert d'appel selon la revendication 1, dans lequel la station de base du premier réseau et le dispositif de commande de réseau d'accès radio du deuxième réseau communiquent par une entité de gestion de mobilité.

4. Procédé pour exécuter un transfert d'appel selon la revendication 1, dans lequel le commencement (322, 324) de la négociation de transfert avec le dispositif de commande d'accès au réseau radio comprend la transmission au dispositif de commande de réseau d'accès radio d'un profil de session incluant des paramètres de commande et de protocole de session utilisés par le dispositif de communication mobile pour l'appel.

5. Procédé pour exécuter un transfert d'appel selon la revendication 1, dans lequel lors du commencement (322, 324) de la négociation de transfert, le dispositif de commande de réseau d'accès radio sélectionne (326) la station de base du deuxième réseau à laquelle l'appel sera transféré.

6. Procédé pour exécuter un transfert d'appel selon la revendication 1, dans lequel le message d'accord de transfert comprend en outre un identifiant assigné destiné à être utilisé par le dispositif de communication mobile.

7. Procédé pour exécuter un transfert d'appel selon la revendication 1, dans lequel le message d'accord de transfert comprend en outre un identifiant de secteur correspondant à un secteur de la station de base cible.

8. Procédé pour exécuter un transfert d'appel selon la revendication 1, dans lequel le message d'accord de transfert comprend en outre des paramètres d'accès aléatoire à utiliser par le dispositif de communication mobile lors du commencement du transfert à la station de base cible.

9. Procédé pour exécuter un transfert d'appel selon la revendication 1, dans lequel le message d'accord de transfert comprend en outre des paramètres de commande et de canaux de trafic dédiés à utiliser par le dispositif de communication mobile lors du commencement du transfert à la station de base cible.

10. Procédé pour exécuter un transfert d'appel selon la revendication 1, dans lequel le message d'accord de transfert comprend en outre un indicateur requis pour l'accès aléatoire pour indiquer si une procédure d'accès aléatoire doit être utilisée par le dispositif de communication mobile lors du commencement du transfert à la station de base cible.

11. Procédé (300) pour exécuter un transfert d'appel d'un premier réseau de communication à un deuxième réseau de communication, où les premier et deuxième réseaux de communication utilisent des interfaces d'air différentes, le procédé comprenant:

recevoir (322, 324) une requête de transfert à un dispositif de commande de réseau radio du deuxième réseau de communication d'une station de base du premier réseau de communication par une entité de gestion de mobilité du premier réseau de communication, la demande de transfert incluant au moins une mesure de cellule de voisinage exécutée par un dispositif de communication mobile fonctionnant dans le premier réseau de communication d'une station de base du deuxième réseau de communication et comprenant en outre un profil de session du dispositif de communication mobile incluant des paramètres de commande et de protocole de session utilisés par le dispositif de communication mobile pour l'appel;

sélectionner (326), au dispositif de commande de réseau radio, une station de base du deuxième réseau de communication pour recevoir l'appel sur la base du profil de session et des ressources disponibles de la station de base du deuxième réseau de communication,

produire un message d'accord au dispositif de commande de réseau radio, le message d'accord incluant un identifiant à utiliser par le dispositif de communication mobile lors du transfert, un identifiant de station de base cible d'une station de base cible du deuxième réseau de communication qui recevra le transfert, et des paramètres de connection à utiliser par le dispositif de communication mobile lors de la connection à la station de base du deuxième réseau de communication; et

transmettre (330, 332), du dispositif de commande de réseau radio à la station de base du premier réseau de communication, le message d'accord de transfert;

où le dispositif de communication mobile utilise l'identifiant de la station de base cible pour transférer à la station de base cible du deuxième réseau de communication en accord avec les paramètres de connection.

12. Procédé pour exécuter un transfert d'appel selon la revendication 11, dans lequel le premier réseau de communication est un système de réseau d'accès radio terrestre universel évolué, E-UTRAN, et le deuxième réseau de communication est un Système Optimisé de Données d'Evolution, EV-DO.

13. Procédé pour exécuter un transfert d'appel selon la revendication 11, dans lequel le message d'accord de transfert comprend en outre un identifiant de secteur correspondant à un secteur de la station de base cible.

14. Procédé pour exécuter un transfert d'appel selon la revendication 11, dans lequel le message d'accord de transfert comprend en outre des paramètres d'accès aléatoire à utiliser par le dispositif de communication mobile lors du commencement du transfert à la station de base cible.

15. Procédé pour exécuter un transfert d'appel selon la revendication 11, dans lequel le message d'accord de transfert comprend en outre des paramètres de commande et de canal de trafic dédiés à utiliser par le dispositif de communication mobile lors du commencement du transfert à la station de base cible.

16. Procédé pour exécuter un transfert d'appel selon la revendication 11, dans lequel le message d'accord de transfert comprend en outre un indicateur requis d'accès aléatoire pour indiquer si une procédure d'accès aléatoire doit être utilisée par le dispositif de communication mobile lors du commencement du transfert à la station de base cible.

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